Raman excitation profiles of several normal modes of 2-benzoylpyridine were measured, and the structural changes encountered on excitations, excited state symmetries, and vibronic couplings among various excited electronic states of the molecule were investigated. Vibrational spectroscopic studies of the molecule were done in detail, and critical investigation on the electronic spectra of the molecule was also carried out. It is shown that the experimentally allowed transitions, corresponding to the band around 262 and 238 nm, occur to the excited states, where the major geometry changes involve both ring CC/CN and CO stretching vibrations.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
December 2009
Emission characteristics of 2,2'-dipyridylketone (DPK) have been studied in the rigid glass matrices of ethanol (EtOH) and methyl cyclohexane (MCH) at 77 K. As in the case of the aromatic analogue benzophenone (BOP), DPK is found to exhibit only phosphorescence emission. Although both BOP and DPK have the lowest triplet states chiefly of n pi* nature, the presence of other triplet states in the neighbourhood of the lowest triplet one is found to play some significant roles in determining the photophysical properties of DPK, specially in the non-polar solvent (MCH).
View Article and Find Full Text PDFDetailed investigation on the vibrational and electronic spectra has been carried out in order to study various properties of 2,2'-dipyridylketone molecule in its ground and excited electronic states. To get insight into the structural and symmetry features of the molecule, Raman excitation profiles of several normal modes have been analyzed. The polarized Raman spectra in different environments along with their IR counterpart have been critically surveyed and different normal modes have been assigned.
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